Streaking into the lead on the first lap of a green-white-checkered-finish, Harvick held off Kasey Kahne, Jeff Gordon and Dale Earnhardt Jr. to win the rain-delayed Cup Series race.
With more than half the field eliminated or hobbled by a series of spectacular accidents, Harvick crossed the finish line a car-length ahead of Kahne and solidified his hold on the top spot in the Cup standings.
Jeff Burton ran fifth, followed by Carl Edwards, Kurt Busch, Reed Sorenson, Mike Bliss and Scott Speed.
The victory was Harvick's second of the season and the 13th of his career. Gordon moved to second in the standings, 212 points behind Harvick. Earnhardt's fourth-place result put him back inside the top 12 with eight races left before the Chase field is set Sept. 11 at Richmond.
Contact from Sam Hornish Jr. sent teammate Kurt Busch into the Turn 4 wall on Lap 159 to set up the two-lap dash to the finish.
Even with his sizable points lead, Harvick wasn't ready to say he should be favored to dethrone four-time defending champion Jimmie Johnson.
"I think until somebody beats him -- until we get to Homestead [the season finale] and that happens, he's still the guy to beat," Harvick said. "For us, we've got to keep working hard. We're in a fortunate position with the start to our season, and we've got to keep working on our cars and trying to make things better, and hopefully, when the stress starts with 10 weeks to go, we'll be as ready as we've ever been."
NASCAR red-flagged the race for more than 20 minutes with 12 laps remaining after a colossal 20-car chain-reaction collision in Turn 3 strewed debris all over the race track. Mark Martin's Chevrolet sustained the most spectacular damage, with the driver of the No. 5 bringing his flaming car to pit road before members of Jimmie Johnson's crew helped him escape from the car.
Among those whose winning chances were destroyed in the wreck were Johnson, Tony Stewart, Juan Montoya, Joey Logano, Brad Keselowski and Ryan Newman.
TNT analyst Kyle Petty called the wreck "the official first fireworks of the Fourth of July," since the incident occurred just after midnight.
David Stremme's spin through Turn 3 on Lap 136 provided an opportunity for pit stops with 23 laps left in the race. Kurt Busch won the race off pit road, but the field couldn't complete a full lap before a crash involving Matt Kenseth and Elliott Sadler slowed the field for the fifth time.
That was just an appetizer, however, for the wild melee that followed on Lap 148.
David Ragan turned sideways in Turn 3 and triggered a Lap 117 wreck that demolished the car of Daytona 500 winner Jamie McMurray and damaged the vehicles of Martin Truex Jr. and Kahne, who slid in oil and hit the wall behind the collision. The wreck knocked Truex out of the race, but Kahne recovered to run in the top 10 before finishing second.
"You had to be aggressive and drive your car sideways all night long," Kahne said. "That's just the way it was. I felt like I had one of the best cars from start to finish -- even hitting the wall I still felt like we had a great car. It was just a wild race. I really enjoyed it."
After climbing to second in the Cup standings, Kyle Busch had his third consecutive star-crossed run. Contact with Montoya's Chevrolet on Lap 104 sent Busch's No. 18 Toyota -- leading the race at the time -- nose-first into the backstretch wall. Busch finished 40th.
The 18 different leaders Saturday night were a record for the event.